Tuesday, April 10, 2007

Ponderosa Parklands

Ponderosa pines are common throughout mountainous regions of the western U.S., found primarily in foothill zones, on lower mountain slopes or atop the higher mesas. These large, aromatic conifers favor dry, sunny areas where they grow in open "parklands," interspersed with meadows of grass, forbs and wildflowers.

In Colorado, ponderosa parklands develop at elevations from 6000 to 9000 feet and are especially common across the Front Range foothills, along the Palmer Divide (north of Colorado Springs) and on the southern flank of the San Juan Mountains. A rich understory of Gambel's oak, mountain mahogany, kinnikinnick, wax current and bitterbush lines the drainages, adding to the floral diversity of these scenic woodlands. On shaded, north-facing slopes, where the soil is cool and moist, dense stands of Douglas fir and Colorado blue spruce predominate.

Mid April is a good time to visit the ponderosa parklands of the Front Range foothills. Western and mountain bluebirds have returned for the summer and are busily hunting for tree cavities in which to nest. Hairy woodpeckers, white-breasted nuthatches and Williamson's sapsuckers noisily roam among the pines, joined by mixed flocks of mountain chickadees, pine siskins and pygmy nuthatches. Not yet moving to higher terrain, red crossbills, red-breasted nuthatches and Cassin's finches may also be found. Other common residents of these parklands include Steller's jays, Townsend's solitaires, violet-green swallows, wild turkeys and dark-eyed juncos; broad-tailed hummingbirds arrive by the end of the month.

Resident mammals include mule deer, golden-mantled ground squirrels, Colorado chipmunks, porcupines, bobcats, black bear and mountain lions. The most characteristic mammal of ponderosa parklands is the Abert's squirrel; these gray or black, tassel-eared squirrels feed exclusively on the inner bark, terminal buds, seeds and fungal growths of ponderosa pines. Active throughout the year, Abert's squirrels are strictly diurnal and aggressively defend their territory.